| 摘要 |
<p>A detector circuit for detecting waves without distortion, which can easily be fabricated totally into a chip. The detector circuit has a circuit configuration similar to a current mirror circuit, in which FETs (1 and 2) are connected together through a resistor (3) between their gates, and an input amplitude-modulated signal is coupled to one end of the resistor (3). The FET (2) is connected at its drain with a low-pass filter (20) that provides a detected output. The FET (2) is also connected at its drain with a resistor (6), the resistance value of which is 0.8 times that of a resistor (5) connected with the drain of the FET (1) so that an unbalanced condition may be created between the FETs (1 and 2). The resistors (5 and 6) have relatively large values so that the FETs (1 and 2) can operate in a saturated region. Thus, only the signal correlated with either the positive or negative envelope of the modulated signal is obtained from the low-pass filter.</p> |
